Glass-drawing bait.



H. F. CLARK.

I GLASS DRAWING BAIT. APPLICATION FILED AuG.2a, 191u.

'1 324,229. Patented m. 9,1919.

WITNESSES mvcm'org Maw/M 62M UNITED s'rarus PATENT orrion.

HENRY CLARK, OF Q AKJ /EONT, PENNSYLVANIA, .ASSIGNOR '10 WINDQVT GLASS MACHINE COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORIOR-ATION OF NEW JERSEY.

To all whom it may concern:

! ing baits, and is designed to provide an improved form of bait whichwill prevent the article being drawn from pulling out of the bait; and whichwill also prevent relative movement between the bait and the engaged portion'of the glass during the draw together with the loose ess resulting from such movement. Suc looseness is ob jectionable for two reasons :First, it is apt to cause leakage of the air from within the article, which is highly objectionable. The air pressure in the article is but slightly above atmospheric and must be under perfeet control during the draw. This is not possible if air leakage, especially of irregular character, exists between the glass and. the bait. Second, any looseness or play of the article in the baitgreatly increases the tendency to breakage 1n takin down the drawn cylinders with the bait attached thereto.

In accordance with my invention, I provide ahollow bait 2, at the lower end of the blow-pipe 3. On the inner glass engaging surface of this bait I form a plurality of annular grooves 4:. These grooves are preferably two in number, althoug3 l more or less may be employed. I prefera ly undercut' the lower wall of the lower groove, as indicated at 5, and similarly undercut the upper wall of the upper groove, ass indicated at 6. In this manner, the lower groove acts' to prevent radial inward movement of the novel 7 of the glass cylinder, while the upper groove effectively prevents the novel Iorm moving outwardly or upwardly.

In use, the bait is preferably immersed in the glass bath to a. sullicientdepth to cause a considerable mass of glass to form over the grpoves 4, relative to the thickness Specification of Letters ma.

ernssnnnwmc BAIT.

Patented Dec. 5- 191-9.

Ap lication filed August 23, 1918. Serial No. 251,100.

of the neck portion 8 of the novel. 'lhis relatively thin neck portion, by reason of its thinness and its exposure to the air will cool more quickly than the thicker head portion;

the bait acting as a heat-retainer for the latter. Consequently there is very little tendency of the bait and novel head to move relatively to each other durin a draw. This is particularly true if the bait is used in the manner described and claimed in the patent to Otis A. Wells, No. 1,301,771, dated April 22, 1919, in which the bait is given a relatively high temperature, short of that at which the glass will fuse to the bait, before it leaves the bath in making a draw.

It will be apparent that my bait gives a very secure anchorage for the novel in starting adraw, as well as throughout the draw,

making it practically impossible for the head or novel to pull out. At the conclusion of the draw, the novel, While not fused to the bait, will be found to be practically free from leosoness. This, together with the in: terlocking action of the grooves 4, causes the novel to be practically sealed against the escape of air during the draw.

The bait may be made of any usual or suitable metal or alloy such as heretofore. 1

employed. The number and form of the grooves 4 may be changed as may also the angle of the inner ncvelsupporting surface of the bait; and other changes may be made without departing from the spirit and scope otmy invention as defined in-the appended claims.

I claim: 1

1. A glass-drawing bait having an internal novel supporting surface surrounding an unobstructed circular opening,- the npvelsupporting surface being provided with a plurality of grooves, substantially as do ving' ovidet "l/lC grooves donovel-supporting surface provided with a plurality of concentric grooves, said grooves having opposite Walls oppositely undercut, substantially as described.

5. A glam-(halving bait having an intarnal novelsupporting surface provided with a plurality 01: grooves, said grooves lnein armlweil 110 'urovirle an inlet-lock r: n l; V c: engagement between the glass and metal to I prevent my relative muvemenl; thereof, sub" 10 stantmlly descmbecl. I

In testmlony Wlmrenl; I have hereunto set my hand.

HENRY F. CLARK. 

